There is a case where simulation using a plant model is performed for the purpose of an optimal operation for a plant such as a chemical plant. PTL 1 discloses a simulation device including a tracking model part, an identification model part, an analysis model part, and a comparison/determination unit. The comparison/determination unit has, in advance, information regarding a parameter which is to be corrected with an identification model in a case where an error occurs in measurement data and prediction data.